The electronics industry has become increasingly driven to meet the demands of high-volume consumer applications, which comprise a majority of the embedded systems market. Embedded systems face challenges in producing performance with minimal delay, minimal power consumption, and at minimal cost. As the numbers and types of consumer applications where embedded systems are employed increases, these challenges become even more pressing. Examples of consumer applications where embedded systems are employed include handheld devices, such as cell phones, personal digital assistants (PDAs), global positioning system (GPS) receivers, digital cameras, etc. By their nature, these devices are required to be small, low-power, light-weight, and feature-rich.
Given the small size of these devices, the amount of storage space can be limited within the device. The use of storage external to the device is one approach to avoiding such limitations. However, transferring data to and from the device to external storage raises potential security issues, not only with regard to the tampering of the data being transferred but also with regard to the possibility of the data being accessed by another unauthorized user. Accordingly, a need exists for ensuring privacy and integrity of data moved from on-chip storage of an embedded system to off-chip storage. The present invention addresses such a need.